FOUS30 KWBC 030801
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
401 AM EDT Wed Jun 3 2026

Day 1
Valid 12Z Wed Jun 03 2026 - 12Z Thu Jun 04 2026

...THERE ARE SLIGHT RISKS OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE NORTHERN PLAINS AND WEST TEXAS INTO EASTERN NEW MEXICO...

...Northern Plains...
Multiple areas of convection producing heavy rainfall and intense
rainfall are expected across portions of the eastern Dakotas into
far western Minnesota during the period. This activity is tied to
an advancing cold front with an axis of anomalous moisture along
and ahead of it. While the setup isn't the most favorable for
training/backbuilding and generally favors more progressive storm
motions, the ingredients do support the latest HREF probabilities
for isolated totals in the 3-5" range. The Slight Risk was 
minimally adjusted to the latest trends. 

...Texas into Oklahoma...
A surface boundary in the vicinity of the area along with a feed 
of Gulf moisture from the southeast will continue the unsettled 
weather pattern. Convection is likely to be ongoing at the start of
the period across far eastern NM into western TX, capable of 
producing locally heavy rainfall and rain rates between 1-2"/hr. 
This activity may then subside by mid day. Convection is then 
expected to blossom further to the northeast across the TX 
Panhandle and west-central Oklahoma. The Slight Risk in that area 
looks good and lines up well with the latest HREF probabilities 
for 3 inches (50-70 percent) and 5 inches (25 percent). 

...South Florida and the Keys...
Approaching frontal boundary and tropical moisture in place will 
contribute to another day of higher coverage and intensity of 
thunderstorms across portions of South Florida urban corridor. HREF
probabilities are elevated for localized 3-5" totals (along with 
hourly rain totals locally between 2-3" where thunderstorms 
persist/repeat, so a Marginal Risk has been maintained. There is 
some signal that the intense rain rates and heavy rainfall may 
approach the entirety of the Keys, so have opted to expand the 
Marginal through Key West. 

Taylor


Day 2
Valid 12Z Thu Jun 04 2026 - 12Z Fri Jun 05 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL ACROSS THE 
PLAINS TO THE UPPER MIDWEST AND SOUTH FLORIDA ...

...Plains to Upper Midwest...
The cold front is expected to set up across Minnesota into the
Plains during the period, acting as the focus for organized
convection. A ramp up in the low-level jet late in the period will
likely be the primary concern for training/repeating rounds of
heavy rainfall as daytime convection should be mainly progressive
and more discrete in nature. The deterministic guidance remains
disperse and ensemble probabilities low to provide confidence for 
any upgrade to Slight Risk at this time, but areas from southwest 
Minnesota into portions of Iowa and eastern South Dakota are of 
concern. For now, the Marginal Risk was maintained and adjusted to 
the latest trends, trimming some from the western to northern boundary.

Further south into the Plains and Texas, the continued moist
southeasterly flow and approaching mid level system out of Mexico
will bring a greater coverage of thunderstorms and the threat of
locally heavy rainfall. Overall organization of the convection is
expected to be on the lower side, but the PW anomalies support
potential for locally intense rain rates and the Marginal Risk. 

...South Florida...
Frontal boundary stalling in the vicinity of the area will remain
the focus for scattered to numerous showers and thunderstorms
capable of producing intense rain rates and locally heavy rainfall
over the highly urbanized corridor. The risk for Thursday shifts a
bit further south across South Florida, mainly centering across the
Miami metro. 

Taylor


Day 3
Valid 12Z Fri Jun 05 2026 - 12Z Sat Jun 06 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE PLAINS, UPPER MIDWEST, TEXAS, AND GULF COAST...

...Upper Midwest...
Low pressure moving across the region with its associated cold
front will be the focus for thunderstorm development Friday into
Friday night with southwesterly flow bringing in an axis of
relatively higher moisture. Aspects of this setup will favor
some training/repeating thunderstorms but the overall motion will
probably lean more progressive. If the front ends up more west to
east oriented and allows for a better setup for training, portions
of the area could need an upgrade to a Slight, but confidence on
that is too low at this point.

...Texas into Gulf Coast...
The mid/upper level feature over Mexico moves into Texas during
this period, continuing another day of generally unsettled weather
and scattered to numerous showers and thunderstorms. If deeper
instability can materialized, pockets of locally heavy rainfall
will be possible due to the intense rain rates. Right now, the
latest deterministic guidance and ensemble probabilities point
toward central to south TX with greater potential. 

Along coastal Louisiana, a surface trough interacting with the
higher moisture in place will bring a higher coverage of
thunderstorms with the potential for intense rain rates and
localized heavy rainfall. 

Taylor
$$
--- SBBSecho 3.28-Linux
 * Origin: Capitol City Online (618:250/10)